As is conventionally known, escalators and moving walkways typically use a handrail in the form of a continuous closed loop or ring, which runs in a continuous circulating manner over suitable guides and the like substantially in synchronism with the escalator treads or the moving walkway. While such a handrail is in the form of a continuous closed loop in its installed and operating condition, it is typically produced from a finite handrail stock material extending longitudinally as a long strip with two terminal ends. To manufacture the finished closed-loop handrail, it is thus necessary to continuously join the two opposite terminal ends of a handrail stock member to each other so as to close the loop. The continuous junction formed in this manner should be substantially smooth and not conspicuous as a junction. Also, the junction must effectively transmit the arising tension continuously along the handrail through this junction, which has been found to be difficult or problematic in practice.
Such a handrail stock member or strip may comprise a handgrip member or main body part made of a polymeric material, and at least one reinforcing layer of longitudinally extending high strength polymer fibers embedded in the polymeric material to take up and transmit tension forces along the longitudinal extending length of the handrail. The handrail stock strip may further include a layer of textile plies arranged crosswise relative to each other and particularly including fibers or threads extending in the transverse or crosswise direction, and still further a low-friction sliding layer forming an inner sliding surface of the handrail. The several layers can be combined or incorporated together to form a one-piece laminated textile structure, which is then embedded and bonded to the polymeric matrix material of the handgrip member or main body part to form the handrail stock member or strip.
With regard to the particular materials, it is known to make the handgrip member or main body part of rubber or a thermoplastic elastomer material, which is reinforced by individual reinforcement fibers of steel (steel cord) or various high strength polymers (e.g. aramid, polyamide, polyester) extending in the longitudinal direction. Further woven fabric layers or plies can additionally be provided to stiffen the profile of the handrail, for example especially also in the transverse or crosswise direction.
To fabricate the closed-loop handrail, such a handrail stock member or strip is cut to the appropriate length, and then the opposite terminal ends thereof are continuously joined at a junction as generally described above. In this regard, it is also necessary to join the ends of the longitudinally extending reinforcement layer to each other, so as to continuously transmit the tension forces through the reinforcing layer across the junction.
To form the continuous junction as mentioned above, including the tension-transmitting junction of the longitudinal reinforcing layer, it is conventionally known to carry out a process as follows. First, it is necessary to partially free and expose the individual reinforcing fibers (and if applicable the woven fabric plies) from the matrix material at the terminal ends of the handgrip member. This is achieved, for example, by cutting away and removing portions of the matrix material. Then, the terminal ends that have been prepared in this manner are laid into a mold, so that the individual fiber ends adjoin and lie against one another laterally or in a sideways direction, while the remaining fabric plies overlap one another. Next, a sufficient quantity of matrix material (e.g. as an uncured liquid) is introduced (e.g. poured or injected) into the mold to fill out the volume of the portion of the handgrip member that has been removed to expose the reinforcing fibers and the like. This matrix material flows around and is pressed into the spaces around the individual reinforcing fibers and the fabric plies so as to embed the fibers and plies therein. Finally, the matrix material is consolidated, cured and hardened under pressure in the mold. This process for fabricating a continuous joint or junction of the terminal ends of the handrail is very complicated, difficult and time consuming, and thus cannot be economically carried out.